I take it your planning on a free range (uncaged) bunny? I'd tend to go for one already neutered as they'll be easier to house train, if you go for a slightly older (6+ month plus) bunny you'll have a better idea of personality too. Rabbits nature can change a lot as they hit puberty so going slightly older you'll get a much better idea of behaviour and you can pick one that will suit living that way. A rescue would definitely be a good way to find just the right bunny and they have a wide variety of breeds and different ages usually.